Non-aqueous electrolyte secondary battery

Abstract

A non-aqueous electrolyte secondary battery that is one aspect of the present disclosure is provided with a positive electrode, a negative electrode, and a non-aqueous electrolyte, the positive electrode having a positive electrode current collector and a positive electrode mixture layer that contains a positive electrode active material and that is formed on the surface of the positive electrode current collector, the positive electrode active material including a lithium-containing composite oxide represented by a prescribed general formula, the lithium-containing composite oxide having secondary particles formed by aggregation of primary particles, Ca being present on the surfaces and in the interiors of the secondary particles, and the proportion of Ca present on the surfaces of the secondary particles being 12-58% relative to the total amount of Ca present on the surfaces and in the interiors of the secondary particles.

1 . A non-aqueous electrolyte secondary battery comprising a positive electrode, a negative electrode, and a non-aqueous electrolyte, wherein
 the positive electrode comprises a positive electrode current collector, and a positive electrode mixture layer formed on a surface of the positive electrode current collector and containing a positive electrode active material,   the positive electrode active material contains a lithium-containing composite oxide represented by general formula Li a Ni b Co c Al d M e Ca f O g  (where 0.9≤a≤1.2, 0.8≤b≤0.95, 0<c≤0.1, 0<d≤0.1, 0≤e≤0.1, b+c+d+e=1, 0.0005≤f/(b+c+d+e+f)≤0.01, 1.9≤g≤2.1, and M is at least one element selected from Mn, Fe, Ti, Si, Nb, Zr, Mo, and Zn),   the lithium-containing composite oxide includes secondary particles formed by agglomeration of primary particles, Ca is present at surface and in interior of the secondary particles, and a ratio of Ca present at the surface of the secondary particles relative to a total amount of Ca present at the surface and in the interior of the secondary particles is 12% to 58%.   
     
     
         2 . The non-aqueous electrolyte secondary battery according to  claim 1 , wherein the ratio of Ca present at the surface of the secondary particles relative to the total amount of Ca present at the surface and in the interior of the secondary particles is 12% to 31%. 
     
     
         3 . The non-aqueous electrolyte secondary battery according to  claim 1 , wherein the ratio of Ca present at the surface of the secondary particles relative to the total amount of Ca present at the surface and in the interior of the secondary particles is 12% to 20%.